Takatukahane

In European Mythologies, they are the female spirits of the sacred river waters. Although she is often described as a mermaid, she is a shapeshifter and can live in human form. She falls in love with a king and decides to live on earth as an ordinary human being.

All Melusine wants from her husband is to give her a little personal space while bathing and leave her alone, not to watch her from the doorway or keyhole.

Because Melusine turns into a mermaid while taking a bath and does not want her husband to find out about it. (Can she have some privacy, mate?!)

However, the curious husband cannot keep this promise -of course- and watches Melusine. Learning this, Melusine gets frustrated and left her husband and never comes back again.